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Old 24-09-2017, 09:52 AM
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Lognic04 (Logan)
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Imaging at F/8 - Worth it?

Hi all,
I have been planning to image ngc 1365, and 1 or 2 of the other galaxies surrounding it, and i have the option to image at f/8 (1330mm) or f/5 (750mm). I asked on another forum which one, and the overwhelming response was f/5, an actual comment being
"go with the shorter for better signal , don't shoot at F/8"
I get what they are saying but for such a small galaxy wouldnt more FL be better?
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Old 24-09-2017, 09:56 AM
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Atmos (Colin)
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It has/is being disucssed in the link below.
http://www.iceinspace.com.au/forum/s...d.php?t=160871

In short. A F/5 with a 5.6 micron pixel sensor will perform exactly the same as a F/8 with 9 micron pixels.

It is aperture and image scale that determine signal strength more than focal length.
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Old 24-09-2017, 11:41 AM
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Lognic04 (Logan)
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Thanks Colin, thats an interesting thread.
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